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Understanding the orbits of giant planets is critical for testing planet formation models, particularly at wide separations (>10 au) where traditional core accretion becomes inefficient. However, constraining orbits at these separations has historically been challenging due to sparse orbital coverage and related degeneracies in the orbital parameters. In this work, we use existing high-resolution (R ∼ 100,000) spectroscopic measurements from CRIRES+, astrometric data from SPHERE, NACO, and Atacama Large Millimeter/submillimeter Array, and combine it with new high-precision GRAVITY astrometry data to refine the orbit of GQ Lup B, a ∼30 MJ companion at ∼100 au, in a system that also hosts a circumstellar disk and a wide companion, GQ Lup C. Including radial velocity (RV) data significantly improves orbital constraints by breaking the degeneracy between inclination and eccentricity that plagues astrometry-only fits for long-period companions. Our work is one of the first to combine high-precision astrometry with the companion’s relative radial velocity measurements to achieve significantly improved orbital constraints. The eccentricity is refined from e=0.47−0.16+0.14 (GRAVITY only) to e=0.35−0.09+0.10 when RVs and GRAVITY data are combined. We also compute the mutual inclinations between the orbit of GQ Lup B, the circumstellar disk, the stellar spin axis, and the disk of GQ Lup C. The orbit is misaligned by 63−14+6 ° relative to the circumstellar disk, 52−24+19 ° with the host star’s spin axis, but appears more consistent ( 34−13+6 °) with the inclination of the wide tertiary companion GQ Lup C’s disk. These results support a formation scenario for GQ Lup B consistent with cloud fragmentation. They highlight the power of combining companion RV constraints with interferometric astrometry to probe the dynamics and formation of wide-orbit substellar companions.

The effects of anandamide on [3H]‐acetylcholine release and muscle contraction were studied on the myenteric plexus‐longitudinal muscle preparation of the guinea‐pig ileum preincubated with [3H]‐choline. Anandamide increased both basal [3H]‐acetylcholine release (pEC50 6.3) and muscle tone (pEC50 6.3). The concentration‐response curves for anandamide were shifted to the right by 1 μM capsazepine (pKB 7.5 and 7.6), and by the combined blockade of NK1 and NK3 tachykinin receptors with the antagonists CP99994 plus SR142801 (each 0.1 μM). The CB1 and CB2 receptor antagonists, SR141716A (1 μM) and SR144528 (30 nM), did not modify the facilitatory effects of anandamide. Anandamide inhibited the electrically‐evoked release of [3H]‐acetylcholine (pEC50 5.8) and contractions (pEC50 5.2). The contractile response to the muscarinic agonist methacholine was not significantly affected by 10 μM anandamide. The inhibitory effects of anandamide were not changed by either capsazepine (1 μM), SR144528 (30 nM) or CP99994 plus SR142801 (each 0.1 μM). SR141716A (1 μM) produced rightward shifts in the inhibitory concentration‐response curves for anandamide yielding pKB values of 6.6 and 6.2. CP55940 inhibited the evoked [3H]‐acetylcholine release and contractions, and SR141716A (0.1 μM) shifted the concentration‐response curves of CP55940 to the right with pKB values of 8.4 and 8.9. The experiments confirm the existence of release‐inhibitory CB1 receptors on cholinergic myenteric neurones. We conclude that anandamide inhibits the evoked acetylcholine release via stimulation of a receptor that is different from the CB1 and CB2 receptor. Furthermore, anandamide increases basal acetylcholine release via stimulation of vanilloid receptors located at primary afferent fibres. British Journal of Pharmacology (2001) 134, 161–167; doi:10.1038/sj.bjp.0704220

This paper explores the integration of tablets, such as the Apple iPad, in university classes and provides recommendations for other instructors to consider when adopting tablet technology. During the trial conducted in the summer of 2011 using iPads, we found that tablets had both academic and social uses, which should be considered when using this technology. The key to successfully adopting tablet technology was to ensure that students remained academically engaged with the device on a regular basis so that they became accustomed to its use. We found that the most useful ways to encourage academic engagement with the device included taking notes during lectures and conducting research during class. The connectivity associated with the devices allowed for enhanced interaction and collaboration among the students. We also found that tablets posed much less of a distraction to students than laptops, i.e., students who used tablets were less likely than laptop users to engage in off-task activities such as instant messaging, social network usage, and watching videos during a lecture. We make five recommendations for faculty who are considering adopting tablets as a mandatory component in their classrooms: (1) Know \"everything\" about the tablet operating system prior to distributing tablets to your students; (2) Decide early on how you would like to use the tablet in your class; (3) Ensure that you work closely with your institution's Information Technology department; (4) Make the tablet an integral component of your class; (5) Describe the features and benefits on the first day; and (6) Carefully consider how to distribute the tablets. (Contains 2 figures and 1 table.)

This study examines earnings inequality by gender and academic field among senior university administrators, including presidents, vice presidents, associate and assistant vice presidents, and deans, using data from the Canadian province of Ontario. While a 4.4 percent earnings gap between male and female administrators is initially identified, much of the gap is explained by earnings inequality across academic fields and by the career experience of the administrators. Administrators who specialize in professional fields such as engineering, health sciences, law, and social work earn between 12 percent and 33 percent more than administrators who specialize in liberal fields in the humanities and social sciences.

Owing to their similarities with giant exoplanets, brown dwarf companions of stars provide insights into the fundamental processes of planet formation and evolution. From their orbits, several brown dwarf companions are found to be more massive than theoretical predictions given their luminosities and the ages of their host stars 1 – 3 . Either the theory is incomplete or these objects are not single entities. For example, they could be two brown dwarfs each with a lower mass and intrinsic luminosity 1 , 4 . The most problematic example is Gliese 229 B (refs.  5 , 6 ), which is at least 2–6 times less luminous than model predictions given its dynamical mass of 71.4 ± 0.6 Jupiter masses ( M Jup ) (ref.  1 ). We observed Gliese 229 B with the GRAVITY interferometer and, separately, the CRIRES+ spectrograph at the Very Large Telescope. Both sets of observations independently resolve Gliese 229 B into two components, Gliese 229 Ba and Bb, settling the conflict between theory and observations. The two objects have a flux ratio of 0.47 ± 0.03 at a wavelength of 2 μm and masses of 38.1 ± 1.0 and 34.4 ± 1.5  M Jup , respectively. They orbit each other every 12.1 days with a semimajor axis of 0.042 astronomical units ( au ). The discovery of Gliese 229 BaBb, each only a few times more massive than the most massive planets, and separated by 16 times the Earth–moon distance, raises new questions about the formation and prevalence of tight binary brown dwarfs around stars. Analysis of the cool brown dwarf Gliese 229 B suggests that it is actually a close binary of two less massive brown dwarfs, explaining its low luminosity and settling the conflict between theoretical predictions and measurements.

This paper explores the growing trend of using mobile technology in university classrooms, exploring the use of tablets in particular, to identify learning benefits faced by students. Students, acting on their efficacy beliefs, make decisions regarding technology’s influence in improving their education. We construct a theoretical model in which internal and external factors affect a student’s self-efficacy which in turn affects the extent of adoption of a device for educational purposes. Through qualitative survey responses of university students who were given an Apple iPad to keep for the duration of a university course we find high levels of self-efficacy leading to positive views of the technology’s learning enhancement capabilities. Student observations on the practicality of the technology, off-topic use and its effects, communication, content, and perceived market advantage of using a tablet are also explored.

Young, low-mass brown dwarfs orbiting early-type stars, with low mass ratios (q ≲ 0.01), appear to be intrinsically rare and present a formation dilemma: could a handful of these objects be the highest-mass outcomes of “planetary” formation channels (bottom up within a protoplanetary disk), or are they more representative of the lowest-mass “failed binaries” (formed via disk fragmentation or core fragmentation)? Additionally, their orbits can yield model-independent dynamical masses, and when paired with wide wavelength coverage and accurate system age estimates, can constrain evolutionary models in a regime where the models have a wide dispersion depending on the initial conditions. We present new interferometric observations of the 16 Myr substellar companion HD 136164 Ab (HIP 75056 Ab) made with the Very Large Telescope Interferometer (VLTI)/GRAVITY and an updated orbit fit including proper motion measurements from the Hipparcos–Gaia Catalog of Accelerations. We estimate a dynamical mass of 35 ± 10 M J (q ∼ 0.02), making HD 136164 Ab the youngest substellar companion with a dynamical mass estimate. The new mass and newly constrained orbital eccentricity (e = 0.44 ± 0.03) and separation (22.5 ± 1 au) could indicate that the companion formed via the low-mass tail of the initial mass function. Our atmospheric fit to a SPHINX M-dwarf model grid suggests a subsolar C/O ratio of 0.45 and 3 × solar metallicity, which could indicate formation in a circumstellar disk via disk fragmentation. Either way, the revised mass estimate likely excludes bottom-up formation via core accretion in a circumstellar disk. HD 136164 Ab joins a select group of young substellar objects with dynamical mass estimates; epoch astrometry from future Gaia data releases will constrain the dynamical mass of this crucial object further.

Giant exoplanets have been directly imaged over orders of magnitude of orbital separations, prompting theoretical and observational investigations of their formation pathways. In this paper, we present new VLTI/GRAVITY astrometric data of HIP 65426 b, a cold, giant exoplanet which is a particular challenge for most formation theories at a projected separation of 92 au from its primary. Leveraging GRAVITY’s astrometric precision, we present an updated eccentricity posterior that disfavors large eccentricities. The eccentricity posterior is still prior dependent, and we extensively interpret and discuss the limits of the posterior constraints presented here. We also perform updated spectral comparisons with self-consistent forward-modeled spectra, finding a best-fit ExoREM model with solar metallicity and C/O = 0.6. An important caveat is that it is difficult to estimate robust errors on these values, which are subject to interpolation errors as well as potentially missing model physics. Taken together, the orbital and atmospheric constraints paint a preliminary picture of formation inconsistent with scattering after disk dispersal. Further work is needed to validate this interpretation. Analysis code used to perform this work is available on GitHub: https://github.com/sblunt/hip65426.

The effects of the nitric oxide (NO) donor S‐nitroso‐N‐acetyl‐DL‐penicillamine (SNAP) and the NO synthase inhibitor L‐NG‐nitroarginine (L‐NOARG) on the electrically evoked [3H]‐acetylcholine release were studied in an epithelium‐free preparation of guinea‐pig trachea that had been preincubated with [3H]‐choline. SNAP (100 and 300 μM) caused small but significant increases of the electrically evoked [3H]‐acetylcholine release (121±4% and 124±10% of control). Resting outflow of [3H]‐ACh was not affected by SNAP. The increase by SNAP was abolished by the specific inhibitor of soluble guanylyl cyclase, 1H‐[1,2,4]oxadiazolo[4,3‐α]quinoxalin‐1‐one (ODQ, 1 μM). The facilitatory effect of SNAP (100 and 300 μM) was reversed into inhibition of release (to 74±4% and to 78±2%) after pretreatment of the trachea with capsaicin (3 μM). ODQ prevented the inhibition. Capsaicin pretreatment alone did not significantly alter the release of [3H]‐acetylcholine. A significant inhibition by SNAP (100 μM) of [3H]‐acetylcholine release (78±3%) was also seen in the presence of the NK2 receptor antagonist SR 48968 (30 nM). L‐NOARG (10 and 100 μM) significantly enhanced the electrically‐evoked smooth muscle contractions, but caused no significant increases of the evoked release from capsaicin pretreated trachea strips. This might indicate that the inhibitory effect of endogenous NO on acetylcholine release is too small to be detected by overflow studies. It is concluded that NO has dual effects on the evoked acetylcholine release. NO enhances release in the absence of modifying drugs, but NO inhibits acetylcholine release after blockade of the NK2 receptor or after sensory nerve depletion with capsaicin. This suggests that NO and endogenous tachykinins act in series to produce an increase in acetylcholine release. British Journal of Pharmacology (2000) 131, 94–98; doi:10.1038/sj.bjp.0703531

This study examines earnings inequality by gender and academic field among senior university administrators, including presidents, vice presidents, associate and assistant vice presidents, and deans, using data from the Canadian province of Ontario. While a 4.4 percent earnings gap between male and female administrators is initially identified, much of the gap is explained by earnings inequality across academic fields and by the career experience of the administrators. Administrators who specialize in professional fields such as engineering, health sciences, law, and social work earn between 12 percent and 33 percent more than administrators who specialize in liberal fields in the humanities and social sciences.